| 摘要 |
<p>In the illustrative embodiments of the invention described, a pneumatic cylinder-and-piston device includes a unitary piston structure for providing two different damping rates in dependency on the direction of movement of the piston within the cylinder. Fluid flow across the piston is preferably controlled, to effect the different damping rates, by use of an elastic sleeve which at one end is carried by the piston and which at the other end engages, suitably under fluid pressure, the inner surface of the cylinder.</p> |
